The invention relates to keyboards, and in particular to keyboards providing adjustment of angle of elevation and height.
Referring to FIG. 1A, a conventional keyboard 10 comprises a plurality of keys 12. The keyboard 10 can be provided with a predetermined inclined angle for ergonomic operation, providing a proper angle of elevation to the keys 12. Furthermore, as shown in FIG. 1B, when the predetermined inclined angle of the keyboard 10 is insufficient, an extra supporting shaft 13 disposed on the bottom thereof can be pulled out to support the keyboard 10, thereby increasing the inclined angle thereof.
As shown in FIG. 1B, the angle of elevation of the keyboard 10 can be adjusted only by means of the supporting shaft 13. The amount by which the angle of elevation of the keyboard 10 can be adjusted is thus fixed. Moreover, when the angle of elevation of the keyboard 10 is adjusted, the keyboard 10 must be lifted, the supporting shaft 13 must be pulled out from a recess on the bottom thereof and rotated to a predetermined position, creating inconvenience of use.
Hence, there is a need for keyboards providing simple and fast adjustment of angle of elevation and operational height.